$ git clone -n https://src.fedoraproject.org/rpms/R-commonmark.git /var/lib/mock/f45-build-6125-346/root/chroot_tmpdir/scmroot/R-commonmark
Cloning into '/var/lib/mock/f45-build-6125-346/root/chroot_tmpdir/scmroot/R-commonmark'...
$ git fetch origin a159b6f2e12ff37aa50d1e40d8e4c948f4c9e9ca:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-commonmark
 * [new ref]         a159b6f2e12ff37aa50d1e40d8e4c948f4c9e9ca -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at a159b6f Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild